EP3963199B1 - Thrust reverser cascade including acoustic treatment - Google Patents

Description

Technical area

The invention relates to the acoustic processing of the sound waves emitted by a turbomachine of an aircraft, and more particularly the processing of the sound waves at the level of the thrust reversers of the turbomachine.

Prior technique

When a turbomachine is in operation, the interaction between the flow and the solid parts of the turbomachine are responsible for generating noise which propagates on either side of the turbomachine.

One of the means of attenuating this acoustic radiation is to integrate acoustic treatment means at the level of the surfaces in contact with the sound waves.

Conventionally, the acoustic treatment of a turbojet engine, and more specifically of the noise radiated by the interaction between the rotor and its environment, is done using absorbent panels placed at the level of the wetted surfaces of the duct in which the waves propagate. sound. The term “wet surfaces” means the surfaces in contact with a fluid flow. These panels are generally composite materials of the sandwich type trapping a honeycomb forming acoustic absorption cells.

It is known for example in the state of the art of acoustic panels with a single degree of freedom, or SDOF for "Single degree of freedom" in English, which have a classic honeycomb structure of acoustic treatment panels filling the walls of the nacelle of a turbomachine.

Due to the operating principle of acoustic treatment panel technologies using resonant cavities, the radial bulk, i.e. the radial thickness, of acoustic treatment panels depends on the treatment frequency targeted to obtain a maximum efficiency in terms of acoustic attenuation.

However, engine architectures increasingly have slower blade wheel rotation speeds and a number of blades on the increasingly small paddle wheels, which leads to a drop in the dominant frequencies of the noise associated with the module comprising the fan and the rectifier stage, or “fan-OGV” module in English for “Outlet Guide Vane”. As a result, the match between the optimum thickness of the acoustic panels and the space available in the nacelles is currently not satisfied.

To slow down an aircraft, a turbomachine generally includes thrust reversers. There are mainly two thrust reverser technologies which are based on gate action. There are two types of gate thrust reversers: fixed gate thrust reversers and sliding gate thrust reversers.

On the figures 1A and 1B are presented schematic views in section in a longitudinal plane of a turbomachine 1 according to a first embodiment known from the state of the art respectively in an inactivated thrust reversal position and in an activated thrust reversal position .

The turbomachine 1 comprises a nacelle 2 with symmetry of revolution around an axis X defining an axial direction D _A , a radial direction D _R and a circumferential direction D _C , a fan 3, a primary stream 4, a secondary stream, a primary rectifier stage 5, a secondary rectifier stage 6, and a gate thrust reversal device 7 comprising a gate 8.

As illustrated on the figures 1A and 1B which represent a turbomachine equipped with a thrust reverser with a fixed grid, in the thrust reversers with a fixed grid, the grid 8 is embedded, that is to say integral, with an upstream part 21 of the nacelle 2 and in sliding connection with a downstream part 22 of the nacelle 2, the upstream and the downstream being defined with respect to the direction of flow of a gas flow F in the turbomachine 1. By translating downstream, the downstream part 22 of nacelle 2 uncovers grid 8 which becomes the only interface between the flow internal to nacelle 2 and the ambient environment in which turbomachine 1 operates.

On the figures 2A and 2B are presented schematic views in section in a longitudinal plane of a turbomachine 1 according to a second embodiment known from the state of the art respectively in an inactive thrust reversal position and in an activated thrust reversal position .

As illustrated on the figures 2A and 2B which represent a turbomachine 1 equipped with a gate thrust reverser in sliding connection, in fixed gate thrust reversers, the gate 8 is in sliding connection with respect to the upstream part 21 of the nacelle 2 and in connection with embedding with respect to the downstream part 22 of the nacelle 2. By translating downstream, the downstream part 22 of the nacelle 2 drives the grid 8 out of the nacelle 2 to position it at the interface between the internal flow to the nacelle 2 and the surrounding environment.

Other thrust reversers according to the prior art are known from FR 3 039 517 A1 And EP 1 978 232 A2 .

The thrust reversers represent both a cost, a mass and a size which are very penalizing for the performance of the propulsion assembly, whereas they are used only at the end of the landing phase. The volume that they use in the nacelle cannot in particular be used, in the state of the art, for the acoustic treatment of the sound waves emitted by the turbomachine.

In propulsion assembly architectures using gated thrust reversers that deploy inside the secondary flow to divert the flow upstream outside the nacelle, a known practice of integrating acoustic treatment classic is to integrate acoustic panels in the cavities of the inverter doors. This practice simply consists of integrating conventional absorber panels into the available volumes, as is done in the fan casing.

Disclosure of Invention

The aim of the invention is to provide a grid-type thrust reversal device which makes it possible both to redirect an air flow towards the upstream side of the turbomachine outside the nacelle and to minimize the pressure losses through the grille when thrust reverser is activated, and to maximize sound absorption efficiency when thrust reverser is inactive.

An object of the invention proposes a grid thrust reverser device for a turbine engine of an aircraft, the device comprising a thrust reversal grid and a box. The grid extends in a first plane defining a first direction and a second direction and has first cavities. The box comprises an opening extending in a plane orthogonal to said first direction and defining a housing in which said grid can be inserted along said first direction. The box and the grid are in translation relative to each other in the first direction between a first position of the thrust reverser device in which the grid is fully disposed in the housing and a second position of the thrust reverser device in which said grid is at least partly outside said housing.

According to a general characteristic of the invention, the box comprises an acoustic treatment panel comprising second cavities extending in a second plane parallel to the first plane, each first cavity facing a second cavity when the inversion device thrust is in the first position to form an acoustic treatment cell.

The thrust reverser grid can be formed by a one-piece annular grid or else by a plurality of grid sections that can be assembled together to form a hollow cylinder with a circular or polygonal base.

Similarly, the acoustic treatment panel can be formed by a one-piece annular panel or else by a plurality of panel sections that can be assembled together to form a hollow cylinder with a circular or polygonal base.

A thrust reverser grid is usually characterized by a metal structure, dimensioned so as to withstand the aerodynamic load to which it is subjected in the thrust reversal phase. This structure also generates pressure drops. A cell is a volume made up of four walls through which a fluid can circulate. Having too high a density of cells can harm the efficiency of the thrust reverser due to too great a resistance to the passage of air.

On the other side, the acoustic panel structures do not undergo aerodynamic stress. The partitions that constitute them are very thin and their low volume makes it possible to optimize the tuning frequency of the panel, that is to say the maximum attenuation frequency.

The two thrust reversal and acoustic processing functions therefore call on very different cell structures.

When the gate thrust reverser device is mounted on a turbojet engine, the first direction corresponds to an axial direction of the turbojet engine and the second direction corresponds to a circumferential direction of the turbojet engine when the grid is at least partially annular or in a direction tangent to the circumferential direction of the turbojet engine when the grid is flat, in other words not curved.

When the thrust reversal device is in its first position where the thrust reversal is inactive, the first cavities of the grid thus extend the second cavities of the acoustic treatment panel, the second cavities being resonant cavities. The superposition of the first cavities and the second cavities in a direction orthogonal to the foreground, for example in a radial direction, makes it possible to form acoustic treatment cells whose height is greater than the height of the second cavity in the direction orthogonal to the first plan. The acoustic treatment cell thus formed by the superposition of a second and a first cavities comprises a treatment height making it possible, on the one hand, to increase the absorption of the acoustic waves, and on the other hand, to absorb lower frequency sound waves than with the acoustic treatment panel alone.

In a first aspect of the thrust reversal device, the thrust reversal grid may comprise first partitions arranged successively along a first direction and parallel to each other and first transverse partitions secant from said first partitions and each extending in planes parallel to each other and parallel to the first direction. The acoustic treatment panel may comprise second partitions arranged successively along the first direction and parallel to each other and secant second transverse partitions of said second partitions and each extending in planes parallel to each other and parallel to the first direction , the first cavities each being defined by two first partitions and two first transverse partitions, the second cavities being each defined by two second partitions and two second transverse partitions. Each first partition can be arranged in the extension of a second partition in a secant direction in the foreground and each first transverse partition can be arranged in the extension of a second transverse partition in the said secant direction in the foreground when the device for reverse thrust is in said first position.

The first partitions are intended to be oriented in a direction secant to the direction of flow of a gas stream inside a turbomachine comprising a thrust reversal device equipped with such a grid. When the grid is mounted on a thrust reversal device on a turbomachine, the first partitions, oriented in an azimuthal or radial direction of the turbomachine, are essential to guarantee the thrust reversal functionality. It is in fact thanks to these first partitions that the flow of air circulating in a vein, inside the nacelle in which the thrust reverser device is mounted, can be captured and redirected towards the upstream of the turbomachine, with respect to the flow direction of the flow inside the nacelle, outside the nacelle.

The first transverse partitions are intended to be oriented in the direction of the gas flow inside a turbomachine comprising a thrust reverser device provided with such a grid. When the grid is mounted on a thrust reversal device on a turbomachine, the first transverse partitions, oriented in an axial direction of the turbomachine, are not essential for the thrust reversal functionality. On the other hand, they allow the formation of resonant cavities making it possible to attenuate the acoustic waves generated by the turbomachine.

In a second aspect of the thrust reverser device, the second partitions of the acoustic treatment panel may comprise a first end facing said thrust reverser grid and a second end opposite the first end. And, for each second bulkhead, the tangent to the second bulkhead at the second end of the second bulkhead may form a first angle with a plane parallel to said first plane when the thrust reversal device is in said first position, the first angle being between 60° and 120°.

This orientation of the second partitions of the acoustic treatment panel at an end opposite the end facing the thrust reversal grid makes it possible to define a substantially radial orientation of the acoustic treatment cells, to avoid penalizing the operation of the resonator of the due to unwanted acoustic reflections on the partitions.

The second partitions of the acoustic treatment panel can thus be curved with possibly one or more inflection points. The use of second curved baffles in the acoustic treatment panel maximizes acoustic treatment efficiency without degrading the thrust reversal functionality of the grille regardless of the positioning of the panel relative to the grille in the orthogonal direction in the foreground.

The second end of the second partitions can thus be either at the entrance to the acoustic treatment cell or the exit from the acoustic treatment cell depending on the positioning of the acoustic treatment panel with respect to the thrust reversal grid in a direction perpendicular to the foreground, that is to say for example in a radial direction.

In a third aspect of the thrust reverser device, the first partitions of the thrust reverser grid may include a first end facing the acoustic treatment panel and a second end opposite the first end. And, for each first bulkhead, the tangent to the first bulkhead at the first end of the first bulkhead may form a first angle with the tangent to the second bulkhead at the first end of the second bulkhead when the thrust reverser device is in said first position, the second angle being between -20° and +20°.

This orientation of the first partitions of the thrust reversal grid at one end opposite the acoustic treatment panel makes it possible to define a relatively small difference concerning the orientation of the cells at the interface between the thrust reversal grid and the acoustic treatment panel, and thus avoid penalizing the operation of the resonator due to unwanted acoustic reflections on the partitions, without disturbing the thrust reversal functionality.

In a fourth aspect of the thrust reversal device, the first partitions of the grid can comprise a first curvature in the direction orthogonal to said first plane and the second partitions of the panel can comprise a second curvature in the direction orthogonal to said first plane distinct from the first curvature. The acoustic treatment cells formed in the first position of the device may include two corrugated walls orthogonal to the first direction and each formed by a first partition and a second partition in the extension of one another.

Said two walls of an acoustic treatment cell thus have an undulation, that is to say a curve with an inflection point, which makes it possible to maximize the acoustic absorption by the cell while maintaining the efficiency of thrust reverser of the thrust reverser grid when the latter is used for thrust reverser.

In a fifth aspect of the thrust reversal device, the first cavities and the second cavities can have the same shape in a section plane parallel to said first plane.

In a sixth aspect of the thrust reversal device, the casing may further comprise a porous interface with a thickness of between 0.5 mm and 20 mm, formed from at least one layer of porous material and arranged at the interface between the acoustic treatment panel and the grille when the thrust reversal device is in the first position, the thickness extending in a direction perpendicular to said first plane.

The addition of a porous interface makes it possible to improve the interface between the two cellular structures, namely the acoustic treatment panel and the thrust reversal grid by ensuring better sealing at the junctions between the partitions of the panel. of acoustic treatment and the bulkheads of the thrust reverser grille, while offering an interesting clearance to improve the sliding of the thrust reverser grille when using the thrust reverser function, it that is to say when the device is in the second position.

In a seventh aspect of the thrust reverser device, the acoustic treatment cells may comprise a height of between 10 mm and 100 mm, the height being measured in a direction perpendicular to the foreground.

In an eighth aspect of the thrust reversal device, the box may comprise a perforated wall and an acoustically reflecting wall each extending parallel to said first plane, the grille and the acoustic treatment panel being arranged between the perforated wall and the wall acoustically reflective when the thrust reverser is in the first position.

In a ninth aspect of the thrust reversal device, which the perforated wall can be directly assembled by gluing to said grid or said acoustic treatment panel.

In a tenth aspect of the thrust reverser device, the acoustic treatment panel may be disposed between the perforated wall and the thrust reverser grid when the thrust reverser device is in the first position.

In an eleventh aspect of the thrust reverser device, the acoustic treatment panel may be disposed between the acoustically reflective wall and the thrust reverser grille when the thrust reverser device is in the first position.

In a twelfth aspect of the thrust reversal device, the grid can be mobile and the box fixed to use the thrust reversal device in a turbomachine provided with a thrust reverser with a grid in sliding connection, or else the grid can be fixed and the movable box to use the thrust reverser device in a turbomachine provided with a fixed gate thrust reverser.

In another object of the invention, there is proposed a turbomachine intended to be mounted on an aircraft, the turbomachine comprising a nacelle with symmetry of revolution defining an axial direction and a radial direction, the nacelle comprising a thickness in the radial direction and a housing extending in the axial direction in its thickness to receive a gate of a gate thrust reverser device.

According to a general characteristic of this object of the invention, the turbomachine may comprise a grid thrust reversal device as defined above, the grid being arranged, when the thrust reversal is not required, in the corresponding housing of the turbomachine nacelle.

In another object of the invention, there is proposed an aircraft comprising at least one turbine engine as defined above.

Brief description of the drawings

• [Fig. 1A-1B] Les figures 1A et 1B, déjà décrites, présentent des vues schématiques en section dans un plan longitudinal d'une turbomachine selon un premier mode de réalisation connu de l'état de la technique respectivement dans une position d'inversion de poussée inactive et dans une position d'inversion de poussée activée.
• [Fig. 2A-2B] Les figures 2A et 2B, déjà décrites, présentent des vues schématiques en section dans un plan longitudinal d'une turbomachine selon un second mode de réalisation connu de l'état de la technique respectivement dans une position d'inversion de poussée inactive et dans une position d'inversion de poussée activée.
• [Fig. 3] La figure 3 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée inactive selon un premier mode de réalisation de l'invention.
• [Fig. 4] La figure 4 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée activée selon un premier mode de réalisation de l'invention.
• [Fig. 5] La figure 5 illustre schématiquement une vue en coupe selon un plan comprenant la direction axiale et la direction circonférentielle d'une grille du dispositif d'inversion de poussée.
• [Fig. 6] La figure 6 illustre schématiquement une vue en coupe selon un plan comprenant la direction axiale et la direction circonférentielle d'un panneau de traitement acoustique du dispositif d'inversion de poussée.
• [Fig. 7] La figure 7 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée dans une position d'inversion de poussée inactive selon un deuxième mode de réalisation de l'invention.
• [Fig. 8] La figure 8 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée activée selon un deuxième mode de réalisation de l'invention.
• [Fig. 9] La figure 9 est un zoom de la figure 7 illustrant l'agencement des premières cloisons et des secondes cloisons dans la première position du dispositif.
• [Fig. 10] La figure 10 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée inactive selon un troisième mode de réalisation de l'invention.
• [Fig. 11] La figure 11 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée activée selon un troisième mode de réalisation de l'invention.
• [Fig.12] La figure 12 est un zoom de la figure 10 illustrant l'agencement des premières cloisons et des secondes cloisons dans la première position du dispositif.
• [Fig. 13] La figure 13 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée inactive selon un quatrième mode de réalisation de l'invention.
• [Fig. 14] La figure 14 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée activée selon un quatrième mode de réalisation de l'invention.
• [Fig. 15] La figure 15 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée inactive selon un cinquième mode de réalisation de l'invention.
• [Fig. 16] La figure 16 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée activée selon un cinquième mode de réalisation de l'invention.
• [Fig. 17] La figure 17 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée inactive selon un sixième mode de réalisation de l'invention.
• [Fig. 18] La figure 18 représente une vue schématique en section selon un plan comprenant la direction axiale et la direction radiale d'un dispositif d'inversion de poussée à grille dans une position d'inversion de poussée activée selon un sixième mode de réalisation de l'invention.

The invention will be better understood from the reading made below, by way of indication but not limitation, with reference to the appended drawings in which:

• [ Fig. 1A-1B ] THE figures 1A and 1B , already described, present schematic cross-sectional views in a longitudinal plane of a turbomachine according to a first embodiment known from the state of the art respectively in an inactive thrust reversal position and in a thrust reversal position. thrust activated.
• [ Fig. 2A-2B ] THE figures 2A and 2B , already described, present schematic cross-sectional views in a longitudinal plane of a turbomachine according to a second embodiment known from the state of the art respectively in an inactive thrust reversal position and in a thrust reversal position. thrust activated.
• [ Fig. 3 ] There picture 3 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an inactive thrust reverser position according to a first embodiment of the invention.
• [ Fig. 4 ] There figure 4 shows a schematic sectional view along a plane comprising the axial direction and the radial direction of a gate thrust reverser device in an activated thrust reverser position according to a first embodiment of the invention.
• [ Fig. 5 ] There figure 5 schematically illustrates a sectional view along a plane comprising the axial direction and the circumferential direction of a gate of the thrust reverser device.
• [ Fig. 6 ] There figure 6 schematically illustrates a sectional view along a plane comprising the axial direction and the circumferential direction of an acoustic treatment panel of the thrust reverser device.
• [ Fig. 7 ] There figure 7 shows a schematic sectional view along a plane including the axial direction and the radial direction of a thrust reverser device in an inactive thrust reverser position according to a second embodiment of the invention.
• [ Fig. 8 ] There figure 8 represents a schematic sectional view according to a plane comprising the axial direction and the radial direction of a reversing device gate thrust in an activated reverse thrust position according to a second embodiment of the invention.
• [ Fig. 9 ] There figure 9 is a zoom of the figure 7 illustrating the arrangement of the first partitions and the second partitions in the first position of the device.
• [ Fig. 10 ] There figure 10 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an inactive thrust reverser position according to a third embodiment of the invention.
• [ Fig. 11 ] There figure 11 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an activated thrust reverser position according to a third embodiment of the invention.
• [ Fig.12 ] There figure 12 is a zoom of the figure 10 illustrating the arrangement of the first partitions and the second partitions in the first position of the device.
• [ Fig. 13 ] There figure 13 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an inactive thrust reverser position according to a fourth embodiment of the invention.
• [ Fig. 14 ] There figure 14 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an activated thrust reverser position according to a fourth embodiment of the invention.
• [ Fig. 15 ] There figure 15 shows a schematic sectional view along a plane comprising the axial direction and the radial direction of a gate thrust reverser device in an inactive thrust reverser position according to a fifth embodiment of the invention.
• [ Fig. 16 ] There figure 16 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an activated thrust reverser position according to a fifth embodiment of the invention.
• [ Fig. 17 ] There figure 17 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an inactive thrust reverser position according to a sixth embodiment of the invention.
• [ Fig. 18 ] There figure 18 shows a schematic sectional view along a plane including the axial direction and the radial direction of a gate thrust reverser device in an activated thrust reverser position according to a sixth embodiment of the invention.

Description of embodiments

On the figures 3 to 12 , the turbomachine 1 comprises a thrust reversal device 70 able to operate according to the operation described on the figures 2A and 2B . The turbomachine comprises a nacelle with symmetry of revolution around an axis X defining an axial direction D _A , a radial direction D _R and a circumferential direction D _C .

On the figures 3 and 4 schematic sectional views are shown along a plane comprising the axial direction and the radial direction of a gate thrust reverser device mounted on an aircraft turbine engine according to a first embodiment of the invention and respectively in a inactive reverse thrust position and in an activated reverse thrust position.

The thrust reversal device 70 comprises a plurality of grids 80 assembled to form a mesh crown. The crown may have a cylindrical base or a polygonal base, the grids 80 extending respectively either in a curved plane comprising the axial direction D _A and the circumferential direction D _C of the turbomachine, or in a straight plane comprising the axial direction D _A and a direction tangent to the circumferential direction D _C .

In the embodiments illustrated, the grids 80 are curved to facilitate the explanation and the reference marks, and extend mainly in a curved plane, hereinafter referred to as the first plane, comprising the axial direction D _A and the circumferential direction D _C .

As shown in the figure 5 which is seen in section of a grid 80 in a section plane parallel to the foreground, each grid 80 comprises a frame 81 inside which extend first partitions 82 in the circumferential direction D _C and first transverse partitions 83 in the axial direction D _A . The frame 81, the first partitions 82 and the first transverse partitions 83 have a height in the radial direction D _R comprised between 5 mm and 50 mm.

The thickness of the first partitions 82 is between 0.5 mm and 5 mm to be thick enough to hold the load cases to which they are subjected, but also as thin as possible to minimize the mass and the pressure drops in the grid. .

The first partitions 82 are azimuthal partitions intended to orient the gas flow F towards the outside of the nacelle 2 and upstream of the turbine engine 1 for thrust reversal when the thrust reversal device is activated. The first transverse partitions 83 are axial partitions intended to define, with the first partitions 82, first cavities 84 for the absorption of the acoustic waves generated by the turbomachine, when the thrust reversal device is inactive.

The distance in the circumferential direction D _C separating two adjacent first transverse partitions 83 from each other is equal to the distance in the axial direction D _A separating two first partitions 82, to thus promote the acoustic propagation in plane waves at the inside the cavities.

The grid 80 comprises, in the axial direction D _A of the turbomachine on which the device 70 is mounted, a first axial end 810 and a second axial end 812. As illustrated in the figures 3 and 4 , in the embodiments illustrated in the figures 3 to 12 and able to operate according to the operation described on the figures 2A and 2B , the second axial end 812 of the grids 80 is fixed to a downstream portion 22 of the nacelle 2 which is mobile relative to an upstream portion 21 of the nacelle 2.

Housed in the upstream part 21 of the nacelle 2 of the turbine engine 1, the thrust reverser device 70 comprises a plurality of boxes 71 assembled to form a ring of panels. The crown may have a cylindrical base or a polygonal base, the boxes 71 extending respectively either in a curved plane comprising the axial direction D _A and the circumferential direction D _C of the turbomachine 1, either in a straight plane, comprises the axial direction D _A and a direction tangent to the circumferential direction D _C .

In the illustrated embodiments the boxes 71 are curved to facilitate the explanation and the references, and extend mainly in a curved plane comprising the axial direction D _A and the circumferential direction D _C .

Each box 71 comprises a perforated wall 72, an acoustically reflecting wall 73 and an acoustic treatment panel 74. The box 71 successively comprises in the radial plane D _R away from the axis of revolution of the turbomachine 1, the wall perforated 72, the acoustic treatment panel 74, a housing 75 configured to accommodate the grille 80, and the acoustically reflective wall 73.

The box 71 further comprises an opening 76 communicating with the housing 75, the opening extending in a plane comprising the radial direction D _R and the circumferential direction D _C at an axial end of the box 71 facing the downstream part 22 from the nacelle 2.

When the thrust reverser is inactive, the thrust reverser device 70 is in a first position illustrated in the picture 3 in which the grid 80 is arranged in the housing 75 of the box 71.

When the reverse thrust is activated, the reverse thrust device 70 is in a second position illustrated in the figure 4 in which the grid 80 is taken out of the box 71 in the axial direction D _A in translation with the downstream part 22 of the nacelle, leaving the housing 75 free at least in part.

The acoustic treatment panel 74 is arranged in the box 71 in a second plane parallel to the first plane in which the grille 80 extends, and the acoustic panel 74 is glued to the perforated wall 72.

The acoustic treatment panel 74 of each box 71 comprises second partitions 742 and second transverse partitions

As shown in the figure 6 which is a sectional view of an acoustic treatment panel 74 in a section plane parallel to the first plane, each acoustic treatment panel 74 comprises a frame 741 inside which extend from the second partitions 742 in the circumferential direction D _C and from the second transverse partitions 743 in the axial direction DA.

The second partitions 742 are azimuthal partitions and the second transverse partitions 743 are axial partitions. The second partitions 742 and the second transverse partitions 743 define between them second cavities 744 for the absorption of the acoustic waves generated by the turbomachine, when the thrust reverser device is in its first position.

The distance in the circumferential direction D _C separating two adjacent second transverse partitions 743 from each other is equal to the distance in the axial direction D _A separating two second partitions 742, to thus promote the acoustic propagation in plane waves at the inside the cavities.

In addition, at the interface between the acoustic treatment panel 71 and the grid 80, each box 70 comprises a porous interface 77 formed of several layers of porous material and having a thickness E in the radial direction D _R of between 0.5 mm and 20 mm to improve the interface between the two cellular structures by ensuring a better seal between the different partitions while facilitating the sliding of the grid 80 in the housing 75 during translations.

When thrust reverser 70 is in its first position as shown in picture 3 , the first cavities 84, the first partitions 82 and the first transverse partitions 83 overlap respectively with the second cavities 744, the second partitions 742 and the second transverse partitions 743 and thus form resonant cavities 710, or acoustic treatment cells, of which the volume of each corresponds to the sum of the volume of a first cavity 84 and of the volume of a second cavity 744. The acoustic treatment cells 710 thus extend over a height H in the radial direction D _R corresponding to the sum the height of the acoustic treatment panel 74, the thickness E of the porous interface 77 and the height of the grid 80. The height H of the acoustic treatment cells is between 10 mm and 100 mm.

In the first embodiment illustrated in the figures 3 and 4 , the first cavities 84 and the second cavities 744 have an identical shape in a section plane comprising the axial direction D _R and the circumferential direction D _C , with first partitions 82 and second partitions 742 each extending purely radially. Thus, in the first position of the thrust reversal device 70, each of the first transverse partitions 83 is not only in the extension of one of the second transverse partitions 743, but more precisely is aligned with one of the second transverse partitions 743.

On the figures 7 and 8 schematic sectional views are shown along a plane comprising the axial direction and the radial direction of a gate thrust reverser device 70 mounted on an aircraft turbine engine according to a second embodiment of the invention and respectively in an inactive reverse thrust position and an activated reverse thrust position.

The thrust reverser device 70 of the second embodiment illustrated in the figures 7 and 8 differs from the first embodiment illustrated in the figures 3 and 4 in that the first transverse partitions 83 of the grid 80 and the second transverse partitions 743 of the acoustic treatment panel 70 each have a curvature in a section plane comprising the radial direction D _R and the axial direction D _A contrary to the first mode of embodiment where the partitions are straight in the radial direction D _R , that is to say where they extend radially.

As illustrated in the figure 9 which is a zoom of the figure 7 illustrating the arrangement of the first partitions 82 and the second partitions 742 in the first position of the thrust reverser device 70 in the second embodiment, the curvature of the second partitions 742 of the acoustic treatment panel 74 is shown in the figure 9 by a first curve C1, and the curvature of the first partitions 82 of the grid 80 is represented by a second curve C2.

If we consider that each partition 742 and 82 is formed by the radial stacking of an infinity of sections, taken in a plane orthogonal to the radial direction D _R , we can define a curve passing through the center of each section and s' extending over the entire height H of the acoustic treatment cell 710 which is formed by the assembly of the first curve C1 with the second curve C2 over the height H of the acoustic treatment cell 7.

The second partitions 742 of the acoustic treatment panel 74 comprise a first end 7420 facing said thrust reversal grid 80 and a second end 7425 opposite the first end 7420 and facing the porous wall 72.

And the first partitions 82 of the grid 80 each comprise a first end 820 facing the acoustic treatment panel 74 and a second end 825 opposite the first end 820 and facing the acoustically reflective wall 73.

The second end 7425 of the second partitions 742 is thus at the entrance to the acoustic treatment cell 710.

In addition, for each second partition 742, in a section plane comprising the axial direction D _A and the radial direction D _R , the tangent T11 to the second partition 742 taken at the second end 7425 forms a first angle A with a parallel plane to said first plane between 60° and 120°, the perforated wall 72 extending along said first plane to the second end 7425 of the second partition 742.

This orientation of the second partitions 742 of the acoustic treatment panel 74 at their second end 7425, which faces the flow circulating inside the nacelle, makes it possible to define a substantially radial orientation of the acoustic treatment cells 710, to avoid penalize the operation of the resonator due to unwanted acoustic reflections on the partitions.

The second partitions 742 of the acoustic treatment panel are therefore curved. The use of second curved partitions 742 in the acoustic treatment panel 74 makes it possible to maximize the efficiency of acoustic treatment without degrading the thrust reversal functionality of the grille whatever the positioning of the panel relative to the grille in the orthogonal direction in the foreground.

In addition, for each first partition 82, in a section plane comprising the axial direction D _A and the radial direction D _R , the tangent T2 to the first partition 82 at its first end 820 forms a second angle B with the tangent T1 to the second partition 742 at the first end 7420 when the reversing device thrust 70 is in said first position. The second angle B is between -20° and +20°.

The first curve C1 defines the first angle A with the first plane. The first angle A is formed between the first plane and the tangent at the end of the first curve C1 opposite the opposite end of the second curve C2.

This orientation of the first partitions 82 of the thrust reversal grid 80 and of the second partitions 742 at the place where they are opposite, that is to say at the interface between the grid 80 and the panel 74, makes it possible to have continuity of the partitions of the acoustic treatment cells 710 and thus to avoid penalizing the operation of the resonator due to undesired acoustic reflections on the partitions, without disturbing the thrust reversal functionality.

The first partitions 82 of the thrust reversal grid 80 all having the same shape and the second partitions 742 of the acoustic treatment panel 74 also all having the same shape, the acoustic treatment cells 710 all have the same profile, this profile following the profile of the first and second partitions 82 and 742.

The first and second curves C1 and C2 define the second angle B. The second angle B is formed between the tangent to the first curve C1 at the end of the first curve C1 facing the second curve C2 and the tangent to the second curve C2 at the end of the second curve C2 facing the first curve C1.

On the figures 10 and 11 schematic sectional views are shown along a plane comprising the axial direction and the radial direction of a gate thrust reverser device 70 mounted on an aircraft turbine engine 14 according to a third embodiment of the invention and respectively in an inactive reverse thrust position and in an activated reverse thrust position.

The thrust reversal device 70 of the third embodiment illustrated in the figures 10 and 11 differs from the second embodiment illustrated in the figures 7 and 8 in that the positions in the radial direction D _R of the acoustic treatment panel 74 and of the grille 80 are reversed.

In the third embodiment, the grid 80 is, in the radial direction D _R , inside the acoustic treatment panel 74. Thus, in the first position of the thrust reverser device 70 illustrated on the figure 10 , the grid 80 extends in the radial direction D _R between the perforated wall 72 of the box 71 and the acoustic treatment panel 74, the porous interface 77 extending between the panel 74 and the grid 80 in the radial direction D _R.

As for the second embodiment, the first transverse partitions 83 of the grid 80 and the second transverse partitions 743 of the acoustic treatment panel 70 each have a curvature in a section plane comprising the radial direction D _R and the axial direction DA.

As illustrated in the figure 12 which is a zoom of the figure 10 illustrating the arrangement of the first partitions 82 and the second partitions 742 in the first position of the thrust reverser device 70 in the second embodiment, the curvature of the second partitions 742 of the acoustic treatment panel 74 is shown in the figure 12 by a first curve C1, and the curvature of the first partitions 82 of the grid 80 is represented by a second curve C2.

If we consider that each partition 742 and 82 is formed by the radial stacking of an infinity of sections, taken in a plane orthogonal to the radial direction D _R , we can define a curve passing through the center of each section and s' extending over the entire height H of the acoustic treatment cell 710 which is formed by the assembly of the first curve C1 with the second curve C2 over the height H of the acoustic treatment cell 7.

The second partitions 742 of the acoustic treatment panel 74 comprise a first end 7420 facing said thrust reversal grid 80 and a second end 7425 opposite the first end 7420 and facing the acoustically reflective wall 73.

And the first partitions 82 of the grid 80 each comprise a first end 820 facing the acoustic treatment panel 74 and a second end 825 opposite the first end 820 and facing the porous wall 72.

The second end 825 of the first partitions 82 is thus at the entrance to the acoustic treatment cell 710.

In addition, for each second partition 742, in a section plane comprising the axial direction D _A and the radial direction D _R , the tangent T11 to the second partition 742 taken at the second end 7425 forms a first angle A with a parallel plane to said first plane between 60° and 120°, the acoustically reflecting wall 73 extending along said first plane at the second end 7425 of the second partition 742.

The first curve C1 defines the first angle A with the first plane. The first angle A is formed between the first plane and the tangent at the end of the first curve C1 opposite the opposite end of the second curve C2.

This orientation of the second partitions 742 of the acoustic treatment panel 74 at their second end 7425 makes it possible to define a substantially radial orientation of the acoustic treatment cells 710, to avoid penalizing the operation of the resonator due to unwanted acoustic reflections on the partitions.

In addition, for each first partition 82, in a section plane comprising the axial direction D _A and the radial direction D _R , the tangent T2 to the first partition 82 at its first end 820 forms a second angle B with the tangent T1 to second bulkhead 742 at first end 7420 when thrust reverser 70 is in said first position. The second angle B is between -20° and +20°.

The first and second curves C1 and C2 define the second angle B. The second angle B is formed between the tangent to the first curve C1 at the end of the first curve C1 facing the second curve C2 and the tangent to the second curve C2 at the end of the second curve C2 facing the first curve C1.

On the figures 13 to 18 , the turbomachine 1 this time comprises a thrust reversal device 70 able to operate according to the operation described on the figures 1A and 1B .

On the figures 13 and 14 are shown schematic views in section along a plane comprising the axial direction D _A and the radial direction D _R of a gate thrust reverser device mounted on an aircraft turbine engine 1 according to a fourth embodiment of the invention and respectively in an inactive reverse thrust position and in an activated reverse thrust position.

The fourth embodiment differs from the first embodiment in that the grid 80 is integral with the upstream part 21 of the nacelle 2 of the turbomachine 1 and the box 71 is made in the downstream part 22 of the nacelle 2. Thus, as shown in the figure 14 , 16 And 18 , in the embodiments illustrated in the figures 13 to 18 and able to operate according to the operation described on the figures 1A and 1B , the first axial end 810 of the grids 80 is fixed to an upstream portion 21 of the nacelle 2 which is mobile relative to a downstream portion 22 of the nacelle 2.

The casing 71 comprises an opening 76 communicating with the housing 75, the opening extending in a plane comprising the radial direction D _R and the circumferential direction D _C at an axial end of the casing 71 facing the upstream part 21 of the nacelle 2.

When the thrust reverser is inactive, the thrust reverser device 70 is in a first position illustrated in the figure 13 in which the grid 80 is arranged in the housing 75 of the box 71.

When the reverse thrust is activated, the reverse thrust device 70 is in a second position illustrated in the figure 14 in which the grid 80 is taken out of the casing 71 in the axial direction D _A , the casing 71 being in translation with the downstream part 21 of the nacelle 2, leaving the housing 75 free at least in part.

On the figures 15 and 16 schematic sectional views are shown along a plane comprising the axial direction D _A and the radial direction D _R of a gate thrust reverser device mounted on an aircraft turbine engine 1 according to a fifth embodiment of the invention and respectively in an inactive reverse thrust position and in an activated reverse thrust position.

The fifth embodiment differs from the second embodiment in that the grid 80 is secured to the upstream part 21 of the nacelle 2 of the turbomachine 1 and the box 71 is made in the downstream part 22 of the nacelle 2.

On the figures 17 and 18 schematic sectional views are shown along a plane comprising the axial direction D _A and the radial direction D _R of a gate thrust reverser device mounted on an aircraft turbine engine 1 according to a sixth embodiment of the invention and respectively in an inactive reverse thrust position and in an activated reverse thrust position. The sixth embodiment differs from the third embodiment in that the grid 80 is integral with the upstream part 21 of the nacelle 2 of the turbomachine 1 and the box 71 is made in the downstream part 22 of the nacelle 2.

The invention thus provides a grid-type thrust reversal device which makes it possible both to redirect an air flow towards the upstream of the turbomachine outside the nacelle and to minimize pressure drops through the grille when thrust reverser is activated, and to maximize sound absorption efficiency when thrust reverser is inactive.

Claims (16)

1. A cascade type thrust reverser device (70) for a turbomachine (1) of an aircraft, comprising a thrust reverser cascade (80) and a casing (71), the cascade (80) extending in a first plane defining a first direction (D_A) and a second direction (D_C) and including first cavities (84), the casing (71) comprising an opening (76) extending in a plane orthogonal to said first direction (D_A) and defining a housing (75) wherein the cascade (80) can be inserted in said first direction (D_A), and the casing (71) and said cascade (80) being in relative translation with respect to one another in the first direction (D_A) between a first position of the device (70) in which the cascade (80) is entirely positioned in the housing (75) and a second position of the device (70) in which said cascade (80) is at least partially outside said housing (75), the casing (71) further comprising an acoustic treatment panel (74) including second cavities (744) extending in a second plane parallel to the first plane, characterized in that each first cavity (84) faces a second cavity (744) when the device (70) is in the first position to form an acoustic treatment cell (710).
2. The cascade type thrust reverser device (70) according to claim 1, wherein said thrust reverser cascade (80) comprises first partitions (82) positioned successively in the first direction (D_A) and parallel to one another and first transverse partitions (83) intersecting said first partitions (82) and each extending in planes parallel to one another and parallel to the first direction (D_A), said acoustic treatment panel (74) comprises second partitions (742) positioned successively in the first direction (D_A) and parallel to one another and second transverse partitions (743) intersecting said second partitions (742) and each extending in planes parallel to one another and parallel to the first direction (D_A), the first cavities (84) each being defined by two first partitions (82) and two first transverse partitions (83), the second cavities (744) each being defined by two second partitions (742) and two second transverse partitions (743), and each first partition (82) is positioned in the continuation of a second partition (742) in a direction intersecting the first plane and each first transverse partition (83) is positioned in the continuation of a second transverse partition (743) in said direction intersecting the first plane when the device (70) is in said first position.
3. The cascade type thrust reverser device (70) according to claim 2, wherein the second partitions (742) of said acoustic treatment panel (74) comprise a first end (7420) facing said thrust reverser cascade (80) and a second end (7425) opposite to the first end (7420), and for each second partition (742), and the tangent (T11) to the second partition (742) at the second end (7425) forms a first angle (A) with a plane parallel to said first plane when the thrust reverser device (70) is in said first position, the first angle (A) being comprised between 60° and 120°.
4. The cascade type thrust reverser device (70) according to claim 3, wherein the first partitions (82) of said thrust reverser cascade (80) comprise a first end (820) facing said acoustic treatment panel (74) and a second end (825) opposite to the first end (820), and for each first partition (82), and the tangent (T2) to the first partition (82) at the first end (820) of the first partition (82) forms a second angle (B) with the tangent (T1) to the second partition (742) at the first end (7420) of the second partition (742) when the thrust reverser device (70) is in said first position, the second angle (B) being comprised between -20° and +20°.
5. The cascade type thrust reverser device (70) according to one of claims 2 to 4, wherein the first partitions (82) of the cascade (80) comprise a first curvature (C2) in the direction orthogonal to the first plane and the second partitions (742) of the acoustic treatment panel (74) comprise a second curvature (C1) in the direction orthogonal to the first plane distinct from the first curvature (C2), the acoustic treatment cells (710) formed in the first position of the thrust reverser device (70) comprising two undulated walls orthogonal to the first direction (D_A) and each formed by a first partition (82) and a second partition (742) in the continuation of one another.
6. The cascade type thrust reverser device (70) according to one of claims 1 to 5, wherein the first cavities (84) and the second cavities (744) have the same shape in a section plane parallel to said first plane.
7. The cascade type thrust reverser device (70) according to one of claims 1 to 6, wherein the casing (71) also comprises a porous interface (77) with a thickness (E) comprised between 0.5 mm and 20 mm, formed of at least one layer of porous material and positioned at the interface between said acoustic treatment panel (74) and said cascade (80) when the thrust reverser device (70) is in the first position, the thickness (E) extending in a direction (D_R) perpendicular to said first plane.
8. The cascade type thrust reverser device (70) according to one of claims 1 to 7, wherein the acoustic treatment cells have a height (H) comprised between 10 mm and 100 mm in a direction (D_R) perpendicular to the first plane.
9. The cascade type thrust reverser device (70) according to one of claims 1 to 8, wherein the casing (71) comprises a perforated wall (72) and an acoustically reflecting wall (73) each extending parallel to said first plane, the cascade (80) and the acoustic treatment panel being positioned between the perforated wall (72) and the acoustically reflecting wall (73) when the thrust reverser device (70) is in the first position.
10. The cascade type thrust reverser device (70) according to claim 9, wherein said perforated wall (72) is directly assembled by gluing to said acoustic treatment panel (74).
11. The cascade type thrust reverser device (70) according to one of claims 9 or 10, wherein the acoustic treatment panel (74) is positioned between the perforated wall (72) and the thrust reverser cascade (80) when the thrust reverser device (70) is in the first position.
12. The cascade type thrust reverser device (70) according to one of claims 9 or 10, wherein the acoustic treatment panel (74) is positioned between the acoustically reflecting wall (73) and the thrust reverser cascade (80) when the thrust reverser device (70) is in the first position.
13. The device (70) according to one of claims 1 to 12, wherein the cascade (80) is movable and the casing (71) is fixed.
14. The device (70) according to one of claims 1 to 12, wherein the cascade (80) is fixed and the casing (71) is movable.
15. A turbomachine (1) intended to be mounted on an aircraft, the turbomachine (1) comprising an axially symmetrical nacelle (2) defining an axial direction (D_A) and a radial direction (D_R), the nacelle (2) including a thickness in the radial direction (D_R) and a housing extending in the axial direction (D_A) in its thickness to accommodate a cascade (80) of a cascade type thrust reverser device,
    characterized in that it comprises a cascade type thrust reverser device (70) according to claim 14, the cascade (80) being positioned, when the thrust reversal is not required, in the corresponding housing of the nacelle (2) of the turbomachine (1).
16. An aircraft comprising at least one turbomachine (1) according to claim 15.

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